rtc: ac100: Assign .num before accessing .hws
Summary
| CVE | CVE-2026-98848 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-18 16:17:39 UTC |
| Updated | 2026-10-21 13:21:49 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: rtc: ac100: Assign .num before accessing .hws Commit f316cdff8d67 ("clk: Annotate struct clk_hw_onecell_data with __counted_by") annotated the hws member of 'struct clk_hw_onecell_data' with __counted_by, which informs the bounds sanitizer (UBSAN_BOUNDS) about the number of elements in .hws[], so that it can warn when .hws[] is accessed out of bounds. As noted in that change, the __counted_by member must be initialized with the number of elements before the first array access happens, otherwise there will be a warning from each access prior to the initialization because the number of elements is zero. This occurs in ac100_rtc_register_clks() due to .num being assigned only after every clkout clock has been stored in .hws[]. With CONFIG_UBSAN_BOUNDS and a compiler that implements __counted_by (GCC 15.1+ or Clang 20.1+), this triggers an array-index-out-of-bounds report during probe, and with CONFIG_UBSAN_TRAP the first store traps. Initialize .num with AC100_CLKOUT_NUM, the number of elements .hws[] was allocated with, right after the allocation. That is the value the loop counter ends up at on the success path anyway, so the provider's behaviour is unchanged. |
Risk And Classification
EPSS: 0.001570000 probability, percentile 0.044430000 (date 2026-10-21)
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected f316cdff8d677db9ad9c90acb44c4cd535b0ee27 e77c5fc1f39fdb06ecd1f55b101eea1e1db2ffef git | Not specified |
| CNA | Linux | Linux | affected f316cdff8d677db9ad9c90acb44c4cd535b0ee27 6bb55381daf1a1bed0657189a1396e7467712525 git | Not specified |
| CNA | Linux | Linux | affected f316cdff8d677db9ad9c90acb44c4cd535b0ee27 160619b38707241e22569f9c983a4b3d0890996a git | Not specified |
| CNA | Linux | Linux | affected f316cdff8d677db9ad9c90acb44c4cd535b0ee27 ad1bf77039cba83373bf1eff3784655e3e3ed2ab git | Not specified |
| CNA | Linux | Linux | affected f316cdff8d677db9ad9c90acb44c4cd535b0ee27 6a4117eee82dd85f11bf898bf66026764011eeb6 git | Not specified |
| CNA | Linux | Linux | affected 6.6 | Not specified |
| CNA | Linux | Linux | unaffected 6.6 semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.160 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.113 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.56 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.2.10 7.2.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.3 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/6a4117eee82dd85f11bf898bf66026764011eeb6 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/160619b38707241e22569f9c983a4b3d0890996a | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/ad1bf77039cba83373bf1eff3784655e3e3ed2ab | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/e77c5fc1f39fdb06ecd1f55b101eea1e1db2ffef | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/6bb55381daf1a1bed0657189a1396e7467712525 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.